In any case, the official start date for your technical startup is the date you incorporate the business. This is obviously important for tax purposes, but this may also dramatically influence how potential investors, customers, and competitors look at you.

My rule of thumb expectation is that it should take two months to set up the legal entity, six months to finalize the business plan, and by the end of the first year, you should have a prototype product ready for customers. At this point, every potential investor will listen. Timelines that vary dramatically from these will be questioned, and they need to have good explanations. Taking too much time may be seen by potential investors as a lack of commitment, or just plain poor management.

For time and effort considerations, I tell clients that a sole proprietorship or partnership is the simplest setup because it basically requires no legal forms. Incorporation as an LLC...